The New England Journal of Medicine recently published the results of a six-year, 10 hospital study conducted in North Carolina between 2002 and 2007. The report can be found online for free here. The study's authors included Dr. Christopher Landrigan, Dr. Gareth Parry, Catherine Bones, Andrew Hackbarth, Dr. Donald Goldmann, and Dr. Paul Sharek.
The study randomly selected 10 hospitals in NC to participate. In those hospitals, researchers randomly pulled 10 patient admissions to the hospital for each quarter from 2002 to 2007. Those records were then reviewed utilizing a "trigger tool" which allows researchers to quickly locate adverse events. Those adverse events were then scrutinized to determine whether the harms were preventable or not preventable.
The authors of the study conclude:
In a statewide study of 10 North Carolina hospitals, we found that harm resulting from medical care was common, with little evidence that the rate of harm had decreased substantially over a 6-year period ending in December 2007.
That embarrassing conclusion was all the more a cause of concern for patient safety advocates since the authors of the report selected North Carolina hospitals for their "high level of engagement in efforts to improve patient safety." Clearly, North Carolina hospitals have a long way to go before they live up to their reputation.
Breakdown of the data and an interesting though experiment on the flip.
The study results indicate that out of 2341 randomly selected patient admissions (2400 planned reviews, appears that 2341 reviews were completed), fully 1 out every 4 resulted in harm to the patient or was considered an "adverse event" by the trigger tool used. Of these 588 "harms" (as the study calls them) 63.1% were "preventable." When one considers that over 40% of these harms ended up requiring prolonged hospitalization, the resulting cost of preventable errors in hospital admissions according to this study would be quite high.
Though the cost is not considered, we can use some back of the envelope calculations to both extrapolate an estimated cost, as well as compare it to the opportunity costs and societal harms resulting from preventable errors in North Carolina hospitals.
In a 1997 study, published by the NC DHHS, there were approximately 750,000 resident patient discharges in North Carolina hospitals and short-stay medical centers throughout the state. The study is available here (.pdf) and is authored by K. Jones-Vessey. Importantly, this study excludes all delivery and newborn baby discharge information. I found the '97 birth rate records through the NC Vital Statistics VOL. 1-1997, which is published by the Epidemiology Division of NC DHHS, a scanned copy available online here. According to the summary table on that publication (page 35 of the pdf), the number of live births in NC for 1997 was approximately 106,000. To keep this exercise simple, lets just say 100,000.
We won't adjust for any population trends, but clearly since '97, NC's population has swelled. So we know these are low figures. 850,000 hospitalizations then, is the number we'll use.
From the NEJM study, we know that roughly 1 in 4 of this results in a harm or "adverse event" according to the trigger tool they used (importantly, the study's authors say that this particular tool was highly reliable). So 25% of the 850,000 hospitalizations, or 212,500 resident patient admissions end in harm to the patient. Again, this is based on 1997 numbers, we know for a fact that the number in today's terms would be higher.
Applying the NEJM rate of 63% to calculate the number of preventable harms, we see that it yields approximately 133,875 preventable harms at NC hospitals. Of these, a little more than 40% (or in real terms, 53,000) are going to result in prolonged hospitalization.
Mortality rates were not disclosed, but let's assume its 1%, for the sake of argument. That would translate into 535 preventable deaths in NC hospitals based on 1997 data. So we know the number today would be higher still. Given the NEJM's sober judgments in this study, I think we can safely say that 1% mortality is unrealistically low. But even if not, even if only 1 out of 100 preventable errors in NC hospitals results in death, that's an astonishingly high real number.
To get a good feel for that, remember that the government of Chile spent approximately $1M per miner (and probably more) in their rescue of the Chilean miners. Chile has a GDP that equates to about 1/3 that of the United States. In essence, they put a value on human life of around $1M in Chilean terms. In American terms, that would be $3M per person. If we accept that number, and multiply it by the postulated 535 preventable deaths, that's a social cost of around $1.6B. If true, that would be a staggering amount of economic drain from NC's already strained economy.
Again, this is "back of the envelope" type stuff. And, to be fair, we are not looking at the number of positive outcomes, and the lives that were saved, in order to properly address the true cost to NC. But let's remember, in 2008, 438 medical malpractice cases were filed in NC. And over the last ten years, patients in NC have only won 51 verdicts. Doctors win over 75% of the time. A good article describing this data can be found at Raleigh's News and Observer here. The average payout over 10 years for plaintiffs has been approximately $316,000.
Clearly, the "drain" here is not to be found in medical malpractice lawsuits. There are so few of them, and the numbers are so low, that changing them fundamentally one way or the other is the equivalent of a drop in the bucket, if that.
Instead, as this NEJM study makes painfully apparent, the real place to focus both our cost-cutting minds and our quality control efforts, is in the delivery of medicine at North Carolina's hospitals. There is definitely a lot of room for improvement there.